docs: def contribute_to_related_class(self, cls, related):
          """
          Called at class type creation. So, this method is called, when
          metaclasses get created
          """
          super(VersionedManyToManyField, self). \
              contribute_to_related_class(cls, related)
          accessor_name = related.get_accessor_name()
          if accessor_name and hasattr(cls, accessor_name):
              descriptor = VersionedManyToManyDescriptor(related, accessor_name)
              setattr(cls, accessor_name, descriptor)
              if hasattr(cls._meta, 'many_to_many_related') and isinstance(
                      cls._meta.many_to_many_related, list):
                  cls._meta.many_to_many_related.append(descriptor)
              else:
                  cls._meta.many_to_many_related = [descriptor]